Turntable lock



June 9, 1931. JIM. KERR 1,808,898

TURNTABLE LOCK Filed Oct. 17, 1929 p am I A TTORNE Y.

Patented June 9, 1931 UNITED STATES PATENT OFFICE JOHN M. KERR, OF BAY CITY, MICHIGAN, ASSIGNOR TO BAY ('JI'IY SHOVELS, INC, 01Ev BAY CITY, MICHIGAN, A CORPORATION OF MICHIGAN TURNTABLE LOCK Application filed October 17, 1929. Serial No. 400,363.

This invention relates to locking mechanism, and more particularly to a lock for use in connection with a full revolving power shovel, whereby the turntable which is movable upon a vertical axis, may be locked against rotation with relation to the power shovel base.

The prime object of the invention is to provide a very simple, substantial, and positive lock which can be mounted on the turntable, and which is engageable with the power shovel base at a point remote from the vertical axis so that the turntable will be locked with relation to the said base.

With the above and other objects in view, the present invention consists in the combination and arrangement of parts, hereinafter more fully described, illustrated in the accompanying drawing, and particularly pointed out in the appended claim, it being understood that changes may be made in the form, size, proportion, and minor details of construction, without departing from the spirit, or sacrificing any of the advantages of the invention.

In the drawings.

Fig. 1 is a fragmentary part sectional longitudinal view through the power shovel, and showing the locking means in locked position, the dotted lines showing the locking means in disengaged position.

Fig. 2 is a fragmentary plan view showing the locking means.

Fig. 3 is an enlarged part sectional edge view of the locking mechanism.

Fig. 4 is a transverse sectional plan view of the locking means and ring gear.

Power shovels are usually mounted on caterpillars so that they may travel with the work on which it is engaged from one location to another, the turntable or superstructure being mounted on the base, and is movable upon a vertical axis, and it is very desirable that when moving from one location to another, or when it is desired to hold the turntable in one position, that the said turntable be locked to the base, so that travel over uneven ground or the tilting of the machine, will not cause the turntable to rotate.

In the drawings, the base is preferably formed of structural members 5 supported on ground engaging endless tracks or caterpillars 6, driven from a power plant, (not shown), in any approved manner, a ring gear 7 is rigidly secured to the base as shown, and.

a vertically disposed shaft 8 projects from the center thereof, and a turntable 9 is mounted thereon, this turntable comprising a fabri cated structural or cast frame 10 provided with a platform 11 in the usual manner.

As above described the turntable is rotatable through 360 on the base, and carries a boom, the necessary hoisting means, and power plant (none of which are shown).

The locking means comprises a vertically disposed slide member 12, shaped as clearly shown in Figs. 3 and 4 of the drawings, and secured to the frame by means of bolts 13 or the like, vertically disposed ways 14: are provided in sai slide, and a locking member 15:

is slidably mounted therein, the edges being mounted in said ways, the lower end having a plurality of teeth 16 secured to or formed integral therewith, and which when in predetermined position, meshes with the teeth of the ring gear.

Ears 17 are provided on the upper end of the locking member and a link 18 is pivotally connected thereto, the opposite end of said link being bifurcated, and is pivotally connected to a curved link 19, which is in turn connected to the leg 20 of a bell crank 21, said bell crank being rotatably mounted on a transversely disposed shaft 22, which is journaled in bearings 23 secured to the face of the platform, the opposite leg of said bell crank being shaped to form a handle 24, which when swung to dotted line position as shown in Fig. l of the drawings, disengages the look from the gear, the upper end of the curved link 19 traveling over beyond the center of the shaft 22 so that said mechanism remains in set position.

From the foregoing description it will be obvious that I have perfected a very simple, substantial, and economical mechanism for locking the turntable of the power shovel with relation to the base.

What I claim is:

A power shovel comprising a mobile base,

a ring gear secured thereto, a turntable mounted on the base and revoluble upon a vertical axis, a Vertically disposed slide secured to said turntable, a locking member slidably mounted therein, and provided with a plurality of teeth for engagement with said ring gear, a link pivotally connected to said locking member, a shaft, a bell crank rotatably journaled thereon, and a curved link connecting said first mentioned link With the bell crank.

In testimony whereof I hereunto affix my signature.

JOHN M. KERR. 

